皮埃尔·伽桑狄Pierre Gassendi

皮埃尔·伽桑狄的父母是弗朗索瓦丝·法布里和路易·安托万加桑德。请注意，加桑德末尾没有“i”并非印刷错误。事实上，伽桑狄最初的名字是伽桑狄加桑德，后来才使用现在熟悉的伽桑狄形式。这个家庭是农民，但有一些迹象表明安托万可能拥有他耕种的土地，这意味着这个家庭并不太穷。伽桑狄在尚泰西耶村度过了童年。他是个相当虚弱的孩子，但从小就表现出对阅读和写作的热情。他的叔叔托马斯·法布里是教区牧师，他给年轻的伽桑狄打下了良好的教育基础。

伽桑狄七岁时被送到迪涅上学，那是山谷对面一个比尚泰西耶大得多的镇子，距离约10公里。他在那里学习拉丁文和算术，除了在里耶上学的一年外，他一直待在迪涅直到1607年[5]：-

十一岁时，他在尚泰西耶的教堂用拉丁文发表了一篇演说，给迪涅主教留下了深刻印象，据说主教曾宣称“这个孩子总有一天会成为他那个时代的奇迹。”在世俗方面，在迪涅上学的最后两年里，年轻的伽桑狄用拉丁文创作了散韵结合的闹剧，供他的同学们在镇上的大宅中演出。

1607年，伽桑狄离开迪涅的学校，回到家乡Champtercier村，在那里度过了接下来的两年。然后在1609年秋天，他前往普罗旺斯地区艾克斯大学，在Père Philibert Fesaye门下学习哲学。他显然是一个出类拔萃的学生，因为当Fesaye缺席时，他请伽桑狄代替他讲课。从1611年起，伽桑狄在Raphaelis教授门下学习神学，作为课程的一部分，他学习了希腊语和希伯来语。当他在艾克斯学习时，他的父亲安托万 Gassend去世了（1611年）。

伽桑狄从1612年4月到1614年担任迪涅学院院长。他于1614年获得阿维尼翁大学神学博士学位，一年后被授予圣职。他已于1614年被任命为迪涅大教堂的较低职位——咏礼司铎。他一直担任此职直到1634年，被提升到更高级别的Prévôt职位。1615年4月，伽桑狄第一次离开普罗旺斯，4月至11月期间在巴黎度过。他去那里是为了解决关于他在迪涅职位的争端。他回到艾克斯，在那里度过了1615-16年的冬天，然后于1616年主持了他的第一次弥撒。

1617年，普罗旺斯地区艾克斯大学的哲学讲席和神学讲席同时空缺。伽桑狄申请了两个讲席，并同时获得了两个。他选择了哲学讲席，把神学讲席让给了他从前的老师菲力贝尔·费萨耶神父。这次被任命为艾克斯大学哲学教授，是在我们上文提到的他在迪涅大教堂所担任的职位之外的。伽桑狄在艾克斯度过了六年，在那里他遇到了尼古拉-克洛德·法布里·德·佩雷斯克（1580-1637），后者成为他的赞助人，多年来在经济上支持他。佩雷斯克曾听过伽利略关于天文学的讲座，并对此产生了浓厚兴趣，以至于他在1610年建立了一座天文台。他雇用约瑟夫·戈蒂埃在那里为他工作，两人是1610年最早观测猎户座星云的人。当伽桑狄到达艾克斯时，他住在约瑟夫·戈蒂埃的家里，他形容戈蒂埃[9]：-

……在比肩所有古代和现代哲学家与数学家方面毫无困难。

Jean-Baptiste Morin也住在戈蒂埃的家里，因为他受雇于佩雷斯克，协助戈蒂埃进行观测。后来Morin和伽桑狄会卷入一场公开争论，但在这一阶段他们是好朋友。伽桑狄很快从戈蒂埃那里学会了天文学，因此佩雷斯克也雇用伽桑狄作为团队的一员，协助他计算木星四颗卫星运行时间的项目。我们也有伽桑狄和戈蒂埃在1618年观测一颗彗星、1620年观测一次月食、1621年观测一次日食的记录。

伽桑狄在艾克斯大学的职位只持续到1623年，当时耶稣会控制了这所大学，他被迫离开。这并不是因为耶稣会对伽桑狄所教授的内容有任何特别的反对，而只是因为他们解雇了所有非耶稣会士。直到1645年他被任命为巴黎皇家学院的数学教授之前，他没有担任任何进一步的学术职位。然而，在我们到达这一点之前，还有伽桑狄二十多年的职业生涯需要考察。他被解除讲席后的第一个行动是前往格勒诺布尔，在那里待到1624年7月，之后他居住在迪涅。在艾克斯教学期间，他将对亚里士多德哲学的反对意见纳入讲座中，并决定出版这些材料。他于1624年在格勒诺布尔出版了Exercitationes I Ⓣ（练习一），这是计划出版的七卷Exercises in the form of paradoxes against the Aristotelians中的第一卷。他写道（例如见[9]）：-

我总是确保我的学生能够正确地捍卫亚里士多德。但与此同时，我也提供了会削弱亚里士多德教条的附录学说。确实，考虑到地点、人物和时代，做前者是必要的。但不省略后者是出于坦诚，因为这些学说提供了拒绝赞同的真正理由。……[我]开始考察其他教派的学说，以查明它们是否能提供更可靠的东西。尽管我发现处处都是困惑，但没有哪个学说比学园派和皮浪主义者所推崇的akatalepsia更让我印象深刻。

伽桑狄于1623年10月首次见到马兰·梅森，当时他访问巴黎。他带去了Peiresc的介绍信，很快伽桑狄和马兰·梅森成为了好朋友。通过马兰·梅森，伽桑狄迅速结识了许多顶尖学者。从那时起直到1648年马兰·梅森去世，每当伽桑狄在巴黎时，他都会拜访马兰·梅森，两人会一起做弥撒。马兰·梅森后来试图说服他放弃数学和神学，转而研究哲学。从巴黎回到普罗旺斯后，伽桑狄写信给伽利略，强烈支持他关于地球绕太阳旋转的论点。伽桑狄原本打算再出版六卷他的Exercitationes Ⓣ（练习一），但此时他决定放弃这个计划。他在1625年至1628年期间在格勒诺布尔、艾克斯和迪涅度过。1628年5月，他再次前往巴黎，通过与Peiresc的联系，他与François Luillier、Dupuy兄弟以及他们圈子中的其他人成为了朋友。伽桑狄和Jacques Dupuy是皇家图书馆的管理员，该图书馆的历史可追溯到十四世纪。它在1567年至1593年间被迁至巴黎，并于1622年编目。伽桑狄和Jacques Dupuy走遍法国为图书馆收集书籍和手稿，在伽桑狄结识这对兄弟后，他在他们的图书馆工作，从事关于伊壁鸠鲁的研究。

他在荷兰待了几个月，于1628年12月前往那里。这是他唯一一次离开法国，他在该国广泛旅行。他的著作Examination of the philosophy of the doctor Robert Fludd于1629年首次在荷兰出版。这本书是应马兰·梅森的要求而写，旨在提出反对弗拉德哲学的论点。1632年，伽桑狄出版了Mercury seen on the face of the sun，其中描述了他对水星中天的观测，他于1631年11月在巴黎观测到这一现象，此前约翰内斯·开普勒在1629年预测了该事件。伽桑狄使用望远镜将太阳的图像投射到纸上，从而能够观测到凌日。伽桑狄继续出版关于哲学和天文学的著作。他相信原子论，并捍卫对自然的机械论解释，例如在On the apparent magnitude of the sun on the horizon and overhead（1635年）中。1637年他的赞助人佩雷斯克去世后，伽桑狄的生活变得更加困难。尽管佩雷斯克在遗嘱中将书籍和数学仪器留给了伽桑狄，但佩雷斯克的侄子拒绝让伽桑狄得到它们。伽桑狄后来撰写了佩雷斯克的传记，于1641年出版；它通常被认为是第一部学者传记。伽桑狄后来撰写了尼古拉·哥白尼、普尔巴赫和约翰·缪勒的传记。

马兰·梅森请伽桑狄审阅勒内·笛卡儿的Meditations ，他照做了，并于1641年写出了Objections。勒内·笛卡儿对伽桑狄的批评并不客气，在Responses中作了尖刻的回击。伽桑狄不打算就此罢休，再次回复，这次是Instantiae，该文于1642年开始在巴黎流传。战线就此划定，两人在非常公开的辩论中各自陈述理由。这并不是伽桑狄当时进行的唯一一场公开辩论。另一场是与Morin的辩论，后者坚持地球位于宇宙中心。伽桑狄是尼古拉·哥白尼和伽利略体系的坚定信奉者，与Morin的争论促使他深入思考太阳中心体系的科学依据。1642年，伽桑狄出版了On the motion impressed by a moving mover。这本书的写作目的是反驳那些声称重物落向地球的方式证明地球不可能在运动的人。1633年伽利略受审令他悲痛，但他继续全力支持伽利略的理论。这本书出版的1642年，实际上正是伽利略在被软禁九年之后去世的那一年。对伽桑狄这部著作的若干攻击，促使他出版了进一步支持伽利略论点的著作，题为On the proportion by which heavy bodies are accelerated。

1645年，在黎塞留枢机主教的推荐下，伽桑狄被授予巴黎皇家学院的数学讲席。虽然通常这是由国王任命的，但当时路易十四只有七岁，他的职责由顾问们执行。伽桑狄在这个人生阶段的健康状况相当差，患有肺部疾病。他接受了数学讲席，条件是在健康状况太差无法留在巴黎时能够返回普罗旺斯；他被任命时这一条件被接受了。他于1645年11月23日发表就职演讲，黎塞留枢机主教在场。他非常成功地履行了职责，讲授天文学主题并进行天文学研究。他得到了让-费利克斯·皮卡德的协助，后者是一位杰出的天文学家。他们观测了1645年8月21日的日食，以及1646年和1647年的月食。伽桑狄的观测结果和讲座被整理并出版为Institutio astronomica juxta hypotheseis tam veterum, quam Copernici et Tychonis Ⓣ（根据古人和尼古拉·哥白尼及第谷·布拉赫的假说进行的天文学训练），于1647年出版。同样在1647年，他出版了Syntagma Philosophicum Ⓣ（哲学分析），该书被翻译成英文并于1699年以Three Discourses of Happiness, Virtue and Liberty出版。这个英文译本开头如下：-

人类天生倾向于追求幸福，他所有行动和努力的主要倾向和设计主要指向那个方向。因此，幸福，或一种免于痛苦和悲惨的生活，是影响和指导我们所有行动和目的的东西，这一点是不可否认的真理，并且是为了获得它们。

正如他所担心的，伽桑狄开始发现他的健康状况使他很难继续教学，因此，按照他任命的条件允许，他于1648年前往普罗旺斯。接下来的几年，他部分时间在迪涅，部分时间在土伦；他发现后者对他的健康特别有益。1649年，他出版了Philosophiae Epicuri Syntagma Ⓣ（伊壁鸠鲁哲学分析），其中包含了他关于伊壁鸠鲁的研究。Lisa T Sarasohn在[11]的序言中这样开头：-

法国神父兼哲学家伽桑狄花了二十多年时间完成他的计划：为伊壁鸠鲁恢复名誉，并将古代原子论者的哲学改造为他自己的体系。

1648年9月19日，Florin Périer和一些朋友在Puy de Dôme山顶进行了布莱兹·帕斯卡建议的一项实验。他们发现山顶水银柱的高度比低1000米的Clermont-Ferrand少85毫米。尽管伽桑狄有肺病，他还是在1650年2月5日与助手François Bernier一起爬上了一座山，证实了Puy de Dôme实验的发现。伽桑狄一直留在普罗旺斯，直到1653年春天，他感觉身体足够好，便与助手François Bernier一起回到巴黎。他找到了一个数学朋友圈子，其中有些是老朋友，有些是新朋友，包括伊斯梅尔·布里阿德、布莱兹·帕斯卡、罗贝瓦尔和吉拉尔·笛沙格。他们每周六上午聚会，可能由于他们的影响，伽桑狄出版了一本匿名小册子，试图让巴黎人民放心，1654年8月12日预测的日食不会导致灾难。他并不完全成功，因为许多巴黎居民在预测日食的那天躲进了地窖。在此期间他还出版了许多其他著作，但在1654年11月他病得很重。第二年春天天气好转时，他恢复了一些，但在1655年8月他又病得很重。医生给他放血，这毫不奇怪地使他更加虚弱。他恳求医生不要再给他放血，但他们继续施行他们的“治疗”。他在Henri-Louis Habert de Montmor家中去世，后者在他最后逗留巴黎期间一直是他的赞助人。他被安葬在Saint Nicolas-des-Champs的Montmor小教堂。他的Complete Works在他去世三年后以六卷本出版。

Antonia Lolordo写道：-

伽桑狄最早的传记作者们对他的性格大致看法一致。他们描述他温和、随和、善于交际、坦率，而且——对于依赖赞助和其他知识分子善意的人来说很重要——谦逊。

Pierre Gassendi's parents were Françoise Fabry and Antoine Gassend. Note that the fact there is no "i" on the end of Gassend is not a misprint. In fact Pierre Gassendi was actually given the name Pierre Gassend and only later used the now familiar Gassendi form. The family were peasant farmers, but there is some suggestion that Antoine may have owned the land he farmed which would mean the family were not too poor. Pierre spent his childhood in the village of Champtercier. He was quite a frail child but showed an enthusiasm for reading and writing at a young age. His uncle, Thomas Fabry, was the parish priest and he gave the young Pierre a good educational grounding.

When Pierre was seven years old he was sent to school in Digne, a much larger town across the valley about 10 km from Champtercier. There he learnt Latin and arithmetic and, except for a year spent at school in Riez, he remained in Digne until 1607 [5]:-

At the age of eleven he so impressed the Bishop of Digne with an oration delivered in Latin at the church in Champtercier that the Bishop is said to have declared that "this child will one day be the marvel of his century." On the secular side, during his last two years at school in Digne the young Gassendi composed prosimetric farces in Latin for his fellow schoolboys to perform in the large houses of the town.

In 1607, Gassendi left school in Digne and returned to his native village of Champtercier where he spent the next two years. Then in the autumn of 1609 he went to the University of Aix-en-Provence to study philosophy under Père Philibert Fesaye. He clearly was an exceptional student for when Fesaye was absent he asked Gassendi to take the lecture in his place. From 1611, Gassendi studied theology under Professor Raphaelis and, as part of the course, he learnt Greek and Hebrew. While he was studying at Aix, his father Antoine Gassend died (in 1611).

Gassendi was Principal at the College of Digne from April 1612 to 1614. He received a doctorate in theology from the University of Avignon in 1614 and was ordained one year later. He had already been appointed to the minor role of Chanoine of the Cathedral in Digne in 1614. He held this post until 1634 when he was elevated to the higher-ranking position of Prévôt. In April 1615 Gassendi left Provence for the first time, spending the period from April to November in Paris. He had gone there to resolve a dispute concerning his position at Digne, He returned to Aix where he spent the winter of 1615-16, then conducted his first mass in 1616.

In 1617 both the Chair of Philosophy and the Chair of Theology fell vacant at the University of Aix-en-Provence. Gassendi applied for both chairs and was offered both. He chose the Chair of Philosophy, giving the Chair of Theology to his former teacher Père Philibert Fesaye. This appointment as professor of philosophy at the University of Aix was in addition to the positions he held in the cathedral in Digne, which we mentioned above. Gassendi spent six years at Aix where he met Nicolas-Claude Fabri de Peiresc (1580-1637) who became his patron, supporting him financially for many years. Peiresc had attended lectures by Galileo on astronomy and had become so interested that he set up an observatory in 1610. He employed Joseph Gaultier to work for him there and the two were the first people to observe the Orion Nebula in 1610. When Gassendi arrived in Aix he lived at the house of Joseph Gaultier whom he described as having [9]:-

... no difficulty in equalling all the ancient and modern philosophers and mathematicians.

Jean-Baptiste Morin also lived in Gaultier's house for he had been employed by Peiresc to assist Gaultier in making observations. Later Morin and Gassendi would become involved in a public dispute but at this stage they were good friends. Gassendi quickly learnt astronomy from Gaultier and so Peiresc also employed Gassendi as part of the team to assist in his project of computing the times of the four moons of Jupiter. We also have records of Gassendi and Gaultier observing a comet in 1618, an eclipse of the moon in 1620, and an eclipse of the sun in 1621.

Gassendi's position at the University of Aix only lasted until 1623 when the Jesuit order took control of the university and he was forced to leave. This was not because the Jesuits had any particular objection to the material that Gassendi was teaching, rather it was just that they dismissed all those who were not Jesuits. He did not hold any further academic posts until 1645 when he was appointed professor of mathematics at the Collège Royale in Paris. However, there is over twenty years of Gassendi's career to look at before we reach that point. His first move on being dismissed from his chair was to travel to Grenoble where he remained until July 1624 after which he resided in Digne. While teaching at Aix he had included his objections to the philosophy of Aristotle in his lectures and he had decided to publish this material. He published Exercitationes I Ⓣ, the first of seven projected volumes of Exercises in the form of paradoxes against the Aristotelians, in Grenoble in 1624. He wrote (see for example [9]):-

I always made sure that my students could defend Aristotle properly. But at the same time, I also provided as appendices doctrines that would undercut Aristotle's dogmas. Indeed, given the place, the characters and the times, it was necessary to do the former. But not to omit the latter was a matter of candour because those doctrines provided true reason for withholding ascent. ... [I] began to examine the doctrines of other sects to find out whether they might offer something sounder. Although I found perplexities everywhere, none of the doctrines impressed me more than the lauded akatalepsia of the Academics and Pyrrhonians.

Gassendi first met Mersenne in October 1623 when he visited Paris. He took with him an introduction from Peiresc and soon Gassendi and Mersenne became good friends. Through Mersenne, Gassendi quickly became acquainted with many leading scholars. From that time on until Mersenne's death in 1648, whenever Gassendi was in Paris he would visit Mersenne and the two would celebrate mass together. Mersenne later tried to persuade him to give up mathematics and theology in favour of philosophy. After returning to Provence from Paris, Gassendi wrote to Galileo with strong support for his argument that the earth revolves round the sun. Gassendi had been intending to produce six further volumes of his Exercitationes Ⓣ but at this time he decided to give up the project. He spent the period between 1625 and 1628 at Grenoble, Aix and Digne. In May 1628 he again travelled to Paris and through his contacts with Peiresc became friendly with François Luillier, the Dupuy brothers, and others from their circle. Pierre and Jacques Dupuy were librarians at the Bibliothèque du Roi, which dated back to the fourteenth century. It had been moved to Paris between 1567 and 1593, and catalogued in 1622. Pierre and Jacques Dupuy travelled throughout France amassing books and manuscripts for the library and, after Gassendi met the brothers, he worked at their library undertaking research on Epicurus.

He spent a few months in the Netherlands, travelling there in December 1628. It was to be his only trip outside France and he travelled widely throughout the country. His work Examination of the philosophy of the doctor Robert Fludd was first published in Holland in 1629. It had been written at Mersenne's request to present the arguments against Fludd's philosophy. In 1632 Gassendi published Mercury seen on the face of the sun, which described his observations of the transit of Mercury which he observed from Paris in November 1631 following the prediction of the event by Kepler in 1629. Gassendi had used a telescope to project the image of the sun onto paper, and so was able to observe the transit. Gassendi continued to publish works on philosophy and astronomy. He believed in atomism and defended a mechanistic explanation of nature, as for example in On the apparent magnitude of the sun on the horizon and overhead (1635). Life became more difficult for Gassendi after his patron Peiresc died in 1637. Although Peiresc left books and mathematical instruments to Gassendi in his will, Peiresc's nephew refused to let Gassendi have them. Gassendi went on to write a biography of Peiresc, published in 1641; it is generally considered the first biography of a scholar. Gassendi later wrote biographies of Copernicus, Puerbach and Regiomontanus.

Mersenne asked Gassendi to review Descartes' Meditations which he did producing Objections in 1641. Descartes did not take kindly to Gassendi's criticisms and replied with a stinging attack in Responses. Gassendi was not going to allow matters to rest there, and replied again, this time with Instantiae which began to circulate in Paris in 1642. Battle lines were drawn, and the two argued their cases in a very public debate. This was not the only public debate that Gassendi was carrying out at this time. The other was with Morin who insisted that the earth was at the centre of the universe. Gassendi was a firm believer in the system of Copernicus and Galileo, and the argument with Morin led to him thinking deeply about the scientific case for a sun centred system. In 1642 Gassendi published On the motion impressed by a moving mover. This book was written to argue against those who claimed that the way heavy bodies fell to the earth proved that the earth could not be moving. He had been saddened by the trial of Galileo in 1633, but had continued to give his full support to Galileo's theories. The year of 1642 when this book was published was actually the year in which Galileo died following nine years of house arrest. Several attacks on this work of Gassendi resulted in his publishing further work supporting the arguments of Galileo entitled On the proportion by which heavy bodies are accelerated.

In 1645, on the recommendation of Cardinal Richelieu, Gassendi was offered the Chair of Mathematics at the Collège Royale in Paris. Although normally an appointment by the king, at this time Louis XIV was only seven years old, and his duties were being carried out by advisors. Gassendi's health was rather poor by this stage in his life, being troubled by a lung complaint. He accepted the Chair of Mathematics on the condition that he would be able to return to Provence when his health was too poor to remain in Paris; he was appointed with this being accepted. He gave his inaugural lecture on 23 November 1645, with Cardinal Richelieu in the audience. He carried out his duties very successfully, lecturing on astronomical topics and carrying out astronomical research. He was assisted by Jean Picard who was an outstanding astronomer. They observed a solar eclipse on 21 August 1645, and lunar eclipses in 1646 and 1647. The results of Gassendi's observations and his lectures were written up and published as Institutio astronomica juxta hypotheseis tam veterum, quam Copernici et Tychonis Ⓣ in 1647. Also in 1647 he published Syntagma Philosophicum Ⓣ which was translated into English and published as Three Discourses of Happiness, Virtue and Liberty in 1699. This English translations begins as follows:-

Mankind having a natural inclination to be happy, the main bent and design of all his actions and endeavours tend chiefly that way. It is therefore an undeniable truth that happiness, or a life free from pain and misery, are such things as influence and direct all our actions and purposes and to the obtaining of them.

As he had feared, Gassendi began to find that his health was making it very difficult for him to continue teaching so, as the conditions of his appointment allowed, he left for Provence in 1648. He spent the following years partly in Digne and partly in Toulon; the latter he found particularly good for his health. In 1649 he published Philosophiae Epicuri Syntagma Ⓣ containing his work on Epicurus. Lisa T Sarasohn begins the Preface of [11] as follows:-

It took the French priest and philosopher Pierre Gassendi more than twenty-five years to complete his project of rehabilitating Epicurus and transforming the philosophy of the ancient atomist into his own system.

On 19 September 1648, Florin Périer and some friends performed an experiment suggested by Blaise Pascal on the summit of Puy de Dôme. They found that the height of a mercury column at the summit is 85 mm less than in Clermont-Ferrand 1000 metres below. Despite Gassendi's lung troubles, he was able to climb a mountain on 5 February 1650 with his assistant François Bernier and confirm the findings of the Puy de Dôme experiment. Gassendi remained in Provence until the spring of 1653 when he felt well enough to return to Paris with his assistant François Bernier. He found a circle of mathematical friends, some old some new, including Ismael Boulliau, Blaise Pascal, Gilles de Roberval and Girard Desargues. They met on Saturday mornings, and probably due to their influence, Gassendi produced an anonymous pamphlet attempting to reassure the people of Paris that the predicted eclipse on 12 August 1654 would not lead to a disaster. He was not entirely successful as many of the inhabitants of Paris hid in their cellars on the day the eclipse was predicted. During this period he also published a number of other works, but in November 1654 he became seriously ill. When the better weather came in the following spring he recovered a bit but in August 1655 he became seriously ill again. He was bled by doctors and this, not surprisingly, left him much weaker. He pleaded with doctors not to bleed him again but they continued to administer their 'cure'. He died at the home of Henri-Louis Habert de Montmor, who had been his patron during his final spell in Paris. He was buried in the Montmor chapel at Saint Nicolas-des-Champs. His Complete Works were published in six volumes three years after his death.

Antonia Lolordo writes:-

Gassendi's first biographers more or less agree about his character. They describe him as gentle, easy-going, sociable, candid, and - importantly for someone dependent on patronage and the good will of other intellectuals - humble.